When did it last have its teeth done, when were its last routine vaccinations - gives you an idea of how much care has been taken of the pony. You can of course check this with its usual vet as well, but the answers can be enlightening.
What is its usual feed - also gives you an idea of the care level, and may give you a hint of any metabolic or digestive issues.
Check you can pick up all four feet easily - gives you an idea of ease of handling and whether the pony is sore on any foot, as well as giving you a closer look at any hoof issues.
See how it reacts when you reach a hand out gently towards its face. Many horses are head shy without other problems, but you don’t necessarily want that for DC.
Run your hand along its back and up and down its legs, from a safe position, to see if it reacts at any particular point or dislikes being touched generally.
If it is already tacked up when you arrive, ask to see it tacked up again to look for discomfort or resistance.
Rudely arrive 10 mins early, with appropriate apologies, in case it has been heavily lunged just before your arrival.
See if it knows that a carrot is a treat - a pony which has had a history of being ridden by children will happily take a carrot, whereas one that has been living out and is green-broken will be less likely to recognise it.